Electric water heater



May 22, 1928.

- 1,670,767 A. A. GRASS! ET AL ELECTRIC WATER HEATER Filed Aug. 50, 1928 fi. 55 1x954 and 35% A. 050. 6224/? Patented May 22, 1928. UNITED STATES PATENT OFFICE.

ANGEL A. GnAssI AND RAFAEL DE OLIVEIRA CEZAB, or BUENOS AIRES, ARGENTINA.

ELECTRIC WATER HEATER. I

' Application filed August 30, 1926. Serial No. 132,498. g a

Our present invention relates to an automatic electrlc water heater'its main ob ect "being to provide anelectric water heater for Zany suitable use, which 'shows'many advantages over th'ose proposed and used hereto fore. 1 p

'In order that our present invention may be clearly understood and easily carried into practice, a preferred embodiment thereof has been shown in the appended drawings wherein,

Figure 1 is a'vertical section of the apparatus showing the main elements thereof.

Figure 2 is a plan view of the heater and Figure 3 is a sideelevation thereof.

Similar characters of reference denote the same or like parts throughout the said drawings.

The apparatus has been shown without its outer envelope and it is obvious that changes in size may be introduced without departing from the scope of. the invention.

The apparatus includes several elements. The heating tube proper consists of a glass tube T through whichwater circulates and within which a resistance B is placed, said resistance consisting of several wound up Nichrom wires and being fixed at its ends to the metal tube C. This tube C consists of two electrically insulated portions. The glass tube fits within the metal tube with an intermediate rubber or insulating tube Gr fixed under pressure. S is the outlet for the hot water and S the inlet they being respectively at the upper part and at the lower of the heating tube.

Under the term of automatic I desire to mean the device by which the electric circuit and the water tlow are automatically regulated. H is the body portion of the automatic device having an inner cylindrical section in which a piston D having acontact member Z thereon is capable oi? reciprocating. Said piston has a rod E secured thereto and is held in its upper position by the action of the springs R. The rod E passes through a stulfing-box K in order to avoid the escape of water which enters the body of the automatic device through the tube. F. N is a metal cross piece mounted upon the rod E and supporting at its: ends the insulating pieces P on which the upper contact members O are fixed, said contacts being the terminals for the wires A, through which current is fed to the apparatus.

On the body of the automatic device there is a metal piece U on which two insulating members Q are fixed, said members carrying the contacts S placed below and separated from the contacts 0. One of the said contacts is connected by a wire V to the copper portion of the tube C while the other contact S is connected by means of another wire V to a contact member I placed within the device at the bottom thereof and electrically insulated therefrom by the pieces J and L.

The tube F is connected to a water pipe while the outlet S is connected to one or more cocks. The subject matter of the automatic device has been included in my copending divisional application filed February 18, 1928, under Serial No. 255,366.

When the cocks are closed the parts will be in the positions shown in the drawings, the heater and the automatic device will be full of water and the electric circuit will be cut oft.

When a tap or cock is opened, the water, due to the pressure set up by the circulation enters the automatic device and presses down the piston D against the action of the springs R and keeps it down so long as the water flows, that is so long as any of the cocks are open.

In these circumstances, the upper contacts 0 will contact with the contacts S", one of which leads to the upper end of the resistance B while the other is connected to the contact 1, against which the contact Z of the piston closes thereby closing also the electric circuit to the lower end of the said resistance B. At the same time the water flows through the automatic device and circulates up to the heating tube through S, and issuing as hot water through the upper end of the said tube.

When the tap is closed, the water remains stationary within the apparatus and automatic device and the piston D is raised by the springs R, thereby cutting oif the current first between the contacts Z and I and then at the contacts 0 and S. No sparking will take place as the first breaking ofi oi the circuit takes place in the water within the automatic device. It is obvious that the closing and cutting off of the electric circuit takes place only under the control of the flowing water and that should there not be any water, the electric circuit will not be closed even when one of the taps or cocks is opened.

The apparatus according to our present invention; has the great adtgantage o'f not requiring anii electric switch 5 and? that i it may be connected to any suitable number of taps orcoek s.

"It is obvious that constructional changes may be introduced without depart: ing from the scope of our present lnventlon which has been clearly-set .t'orth'lin therap:v A pended claiming clauses.

Having nowf fully described and v ascertained the nature A of our present invention and inwhat manner the. same isto be carried intopractice,'1\ve declare that what .We claim and desire'to protect byiLetters Patent is:

1, An electric -'\vater heater comprising a glass tube an insulating tube surrounding {said glass tube apair ofinet-al tubes lnounteduroundsaid insul-ating' tube; said metal tubes being spaced from each-other; and a heating Wire in said-glass tube, one end connected to one -metal tube and the 7 other end connected to the otlierrmetal tube'to coinplete an electric circu -it said glass tube be- 1 ing adapted Q to i have water' circulated there- 7. through which is heated by the'wire.

t -E D ele r heatemqmpri ing a --g1ass tube an insulating 'tube surrounding said glassi tube; a pair of metal tubes mounted around said insulating tube, said metal an electric circuit, gsaidgla s tub being adapted to ';have water circulated :there: through which is heated by the Wire; andzan inlet .-ffor ;the waterat the outer end of one 1ofthemetal,;.tubes,,and;an outlet for-the water at the outer end of, the other; metal jtnbe.

Intestimony whereof ,We aflix ourjsig-natures. V

ANGEL AGRASSI. 1 RAFAEL DE OLIV IRA 

